Phthalocyanines

ABSTRACT

A phthalocyanine pigment mixture which contains a compound of the formula:   IN WHICH Pc represents a phthalocyanine residue, the benzene nucleus A is substituted by at least one alkyl group having up to four carbon atoms, and n is a whole number from 1 to 4; process for the stabilisation of phthalocyanine pigments which comprises incorporating therewith at least one compound of formula (I); and paints, lacquers, enamels and plastic materials coloured by means of a phthalocyanine pigment mixture containing a compound of formula (I).

nited States Patent 1 Kienzle et a1.

[- PHTHALOC'YANINES [75] Inventors: Jean Andre' Paul Kienzle; MichelErnest Antoine Huille, both of Creil; Louis Antoine Cabut, NogentS/Oise, all of France [73] Assignee: Ugine Kuhlmann, Paris, France [22]Filedi Nov. 22, 1971 [21] Appl. No.: 201,201

[30] Foreign Application Priority Data Nov. 20, 1970 France 7041759 [52]U.S. Cl 106/288 Q, 260/3145 [51] Int. Cl C08h 17/14 [58] Field of Search106/288 Q [56] References Cited UNITED STATES PATENTS 3,646,003 2/1972Lamure 106/288 Q FOREIGN PATENTS OR APPLICATIONS 758,485 5/1967 Canada106/288 0 949,739 2/1964 Great Britain 106/288 Q 1 Oct. 23, 1973 PrimaryExaminerDelbert E. Gantz Assistant Examiner-James W. HellwegeAttorney-Francis C. Browne et al.

[57] ABSTRACT A phthalocyanine pigment mixture which contains a compoundof the formula:

13 Claims, No Drawings 1 PHTHALOCYANINES The invention relates tophthalocyanine pigment mixtures which are s'tabletowai'dscrystallisation.

It is known that the a form of copper phthalocyanine has thedisadvantage of c'rys tallising. The crystallisation or growth of thecrystals takes place slowly in the cold and rapidly in the hot oncontact with aromatic hydrocarbons. For example, in a paint kept in acan and containing such solvents, the micro-crystals of the pigment areslowly changed into larger crystals with a considerable loss ofcolouring power. This phenomenon constitutes an objection against theuse of this substance in inks, paintsand plastics. The crystallisationof the a volves ar'eduction of the colouring power.

It has now been found that the crystallisation can be prevented bymixing phthalocyanines with a compound of the generallformula:

in which Pc represents a phthalocyanine residue, the benzene nucleus Ais substituted by at least one alkyl group having up to four carbonatoms and n is a whole number from 1 to 4, I

The phthalocyanine of residue Pc may or may not be metallised. Thephthalocyanineof the residue Pcmay be copperphthalocyanine :in'its a or)9 form or a halogenated phthalocyanine derivative especially achlorinated derivative containing up to 4'percent of chlorine.

Examples of compounds of the general formula (I) includetris-(p-toluidinomethyl)-copperphthalocyanine, tris-( xylidinomethyl)-copperphthalocyanine,' and monochlorinated tris-(p-t'oluidinomethyl copperphthalocyanine.

The compounds of formula (I) may be obtained by reacting achloromethylated phthalocyanine with an amine of the general formula:

in which A is as defined above.

The incorporation of at least one stabilising phthalocyanine of formula(I)"in the phthalocyanine or phthalocyanines to be stabilised may beeffected by simple mixing of the two types of phthalocyanines (a) in anaqueous suspension at ambient temperature, followed by filtration,draining and drying,- or (b) by dry grinding in the presence of a salt,taking up in hot water to remove the salt and filtering, or (c) bykneading the press-pastes with the, stabilising phthalocyanine, or (d)mula (II).

The amount of the compound of formula (I) preferably incorporated is lto 20 percent by weight based on the total weight of pigment to bestabilised plus the compound of formula (I).

The mixtures of a copper phthalocyanine and/or monochlorinated [3 copperphthalocyanine with at least one compound of formula (I) do notcrystallise in the solvents and are stable to flocculation in varnishesand paints. They also have the advantage of having good resistance toleaching out of the mixture by solvents, which was quite unexpectedtaking into account the solubility of the compounds of formula (1) inaromatic solvents such as xylene or toluene.

They are also fast to overvarnishing. This property is verified by theabsence of migration of pigments into white paint used to mask an areacoloured with a paint based on phthalocyanine.

The following Examples, in which the parts and percentages are byweight, illustrate the invention without restricting it. I I

EXAMPLE 1 Forty parts of the B form of copper phthalocyanine (ColourIndex 74,160) are suspended in 200 parts of chlorosulphonic acid and 100parts of 96 percent sulphuric acid. parts of paraformaldehyde are addedat to C and the mixture is heated at 90 to 95C for about 2 hours. It isleft to cool to ambient temperature and then poured on a mixture ofwater and ice. The precipitate formed is filtered off, washed until thewashings are neutral and dried at 40 to 50C.

A product is obtained with a chlorine content of 14.55 percent whichcorresponds to (chloromethyl)-copper phthalocyanine.

Twenty-five parts of this compound are mixed with parts ofparatoluidine. The mixture is heated to 95 to 100C with stirring until asample upon dilution with alcohol, filtration and washing with water nolonger contains chlorine. After heating for 15 hours, the reac- Theproportion of nitrogen in the product corresponds to that intris-(4-methyl-phenylaminomethyl)-copper phthalacyanine.

Analysis: N calculated for C l-l N cu 16.52%

Found 15.9%

Five parts of tris-(4-methyl-phenylaminomethyl)- copper phthalocyanineare added to a suspension of 100 parts of copper phthalocyanine (ColourIndex 74,160) obtained in the a form by dissolving the crudephthalocyanine (B form) in sulphuric acid and reprecipitating in water.This suspension is stirred for several hours at the ambient temperature.The pigment mixture is filtered off, drained and dried. The dry pigmeritis easily reduced to a soft powder. The examination of its stability iseffected as follows:

l g of the pigment mixture is dispersed in 10 ml of xylene and thedispersion refluxed for 2 hours. After cooling, the product is separatedby filtration and dried after washing with ethanol. The X-ray diagramshows that the pigment mixture still consists of 100 percent of tristhea form. During the same test the a form of the copper phthalocyanine (aspure product) recrystallises completely in the form of large needles ofthe B form when the methylphenylaminc-methylated derivative is notpresent.

In addition to its good stability towards crystallisation, this pigmenthas a good stability towards flocculation. Verification of this iseffected as follows:

One part of pigment mixture is dispersed in 100 parts of nitrocellulosevarnish and parts of this dispersion are mixed with 25 parts of whitepaint containing a pigment with a titanium oxide base. The colouredsuspension, stored in a glass cylinder, undergoes no modification inintensity at the end of several weeks, although the phthalocyanineobtained under the same conditions in the form of the pure produce andapplied in the same way gives a suspension which is decolourised at theend of a few days.

EXAMPLE 2 10 parts of tris-(chloromethyl)-copper phthalocyanine areadded to 50 parts of mesidine. The mixture is heated at 90 to 95C withstirring for about hours. It is allowed to cool to 50 to 60C and dilutedwith acetone. The phthalocyanine derivative is filtered off, washed withacetone, then with water and dried. 12.8 parts of a product which onlycontains small traces of chlorine are obtained. The proportion ofnitrogen in the product corresponds to that intris-(2,4,6-trimethylphenylaminomethyl)-copper phthalocyanine.

Analysis: N calculated for C l-l -,N, Cu 16.04%

Found 15.4%

A mixture comprising 125 parts of crude copper phthalocyanine (B form),100 parts of monochlorocopper phthalocyanine (Colour Index 74,250, Bform), parts of tris-(2,4,6-trimethyl-phenylaminomethyl)- copperphthalocyanine and 1,000 parts of sodium sulphate is ground in a ballmill for about 40 hours.

The ground mass is stirred into 10,000 parts of hot water, filtered off,washed until the salt is completely eliminated, and dried. A pigmentmixture stable to recrystallisation and flocculation in paints isobtained.

Example 3 100 parts of press paste of the B form of copperphthalocyanine, containing 25 parts of dry pigment, is intimatelykneaded with 1 part oftris-(2,6-dimethylphenylaminomethyl)-copperphthalocyanine. The mixtureis dried at 60C. and then reduced to a fine powder.

Compared with the pigment from the same pressed paste without thetris-methylated derivative, this pigment composition has an improvedresistance to the growth of crystals on contact with organic solvents.

Example 4 A mixture comprising 240 parts of crude copper phthalocyanine(B form), 10 parts of tris-(4-methylphenylaminomethyl)-copperphthalocyanine, 1,000 parts of a water-soluble mineral salt such assodium sulphate or calcium chloride and 50 parts of trichloroethylene isground in a ball mill for 48 hours.

The mixture is taken up in 30,000 parts of hot water and filtered. Apigment of the B form is obtained which, compared with the crudephthalocyanine without the tris-methylated derivative, has an excellentresistance to recrystallisation in boiling xylene.

Example 5 parts of a non-chlorinated copper phthalocyanine pigment (aform), which is obtained by grinding a crude phthalocyanine with sodiumsulphate, and 5 parts of tris-(4-methyl-phenylaminomethyl)-copperphthalocyanine are mixed for 10 hours. The resulting pigment is stableto increase in crystallinity in the organic solvents. In addition, ithas good rheological properties when it is incorporated into inks forhelioengraving.

Example 6 240 parts of a crude copper phthalocyanine containing 2.8percent of chlorine and 1,000 parts of sodium sulphate are ground in aball grinder for 48 hours. The ground mass is diluted in 10,000 parts ofwarm water and, 10 parts of tris-( 2 ,6-dim ethylphenylaminomethyl)copper phthalocyanine are added. The product is filtered, washed untilthe salt is completely eliminated and dried. A pigment is obtainedwhich, compared with that obtained under the same conditions in theabsence of tris-(2,6-dimethylphenylaminomethyl)-copper phthalocyanine,shows an improved resistance to increase in crystallinity in xy lene andto flocculation in painting.

We claim:

1. A phthalocyanine pigment mixture which contains a compound of theformula:

in which Pc represents a phthalocyanine residue, the benzene nucleus Ais substituted by at least one alkyl group having up to four carbonatoms, and n is a whole number from 1 to 4.

2. A mixture as claimed in claim 1 wherein n is 3 or 4 in formula (I).

3. A mixture as claimed in claim 1 wherein the residue P0 is copperphthalocyanine in its aor B- form.

4. A mixture as claimed in claim 1 wherein the residue Fe is ahalogenated phthalocyanine derivative.

5. A mixture as claimed in claim 1 which comprises a copperphthalocyanine and a compound of formula (I).

6. A mixture as claimed in claim 1 which comprises the monochloroderivative of a copper phthalocyanine and a compound of formula (I).

7. A mixture as claimed in claim 1 which comprises 95 percent of copperphthalocyanine in a a form and 5 percent oftris-(4-methyl-phenylaminomethyl)- copper phthalocyanine.

8. The mixture comprising 96 percent of copper phthalocyanine in B formand 4 percent of tris-(4- methyl-phenylaminomethyl)- copperphthalocyanine.

9. A mixture as claimed in claim 1 which comprises 25 parts of copperphthalocyanine in B form and 1 part oftris-(2,6-dimethyl-phenylaminomethyl)-copper phthalocyanine.

10. A mixture as claimed in claim 1, wherein there is l to 20 percent,based on the total weight of pigment to be stabilised plus the compoundof formula (1), of the compound of formula (I) as defined in claim 1.

11. A process for the stabilisation of phthalocyanine pigments whichcomprises incorporating therewith at least one compound of the formula:

in which Pc represents a phthalocyanine residue, the benzene nucleus Ais substituted by at least one alkyl group having up to four carbonatoms, and n is a whole tered.

2. A mixture as claimed in claim 1 wherein n is 3 or 4 in formula (I).3. A mixture as claimed in claim 1 wherein the residue Pc is copperphthalocyanine in its Alpha - or Beta - form.
 4. A mixture as claimed inclaim 1 wherein the residue Pc is a halogenated phthalocyaninederivative.
 5. A mixture as claimed in claim 1 which comprises Alphacopper phthalocyanine and a compound of formula (I).
 6. A mixture asclaimed in claim 1 which comprises the monochloro derivative of Alphacopper phthalocyanine and a compound of formula (I).
 7. A mixture asclaimed in claim 1 which comprises 95 percent of copper phthalocyaninein a Alpha form and 5 percent oftris-(4-methyl-phenylaminomethyl)-copper phthalocyanine.
 8. The mixturecomprising 96 percent of copper phthalocyanine in Beta form and 4percent of tris-(4-methyl-phenylaminomethyl)-copper phthalocyanine.
 9. Amixture as claimed in claim 1 which comprises 25 parts of copperphthalocyanine in Beta form and 1 part oftris-(2,6-dimethyl-phenylaminomethyl)-copper phthalocyanine.
 10. Amixture as claimed in claim 1, wherein there is 1 to 20 percent, basedon the total weight of pigment to be stabilized plus the compound offormula (I), of the compound of formula (I) as defined in claim
 1. 11. Aprocess for the stabilisation of phthalocyanine pigments which comprisesincorporating therewith at least one compound of the formula:
 12. Aprocess as claimed in claim 11 wherein the phthalocyanine pigment andcompound of formula (I) are mixed in aqueous suspension at the ambienttemperature, filtered, and dried.
 13. A process as claimed in claim 11wherein the dry phthalocyanine pigment and the compound of formula (I)are ground in the presence of a water-soluble mineral salt, the mixturedispersed in hot water and filtered.